Sat 2015 Practice Test #1 Answer Explanations

The correct answer is 7. 
Subtracting the left and right sides of 
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+ 
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+ 2
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(
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+ 2
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)
 
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+ 
y 
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y
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in 
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+ 
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equivalent to 
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QUESTION 19 
_
The correct answer is 5
4 or 0.8.
By the complementary angle
relationship for sine and cosine, sin(
[r FRVrơ[
°). Therefore, 
_
FRVrơ[
°) = 45
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may be gridded as the correct answer. 
Alternatively, one can construct a right triangle that has an angle of 
_
mea sure 
[
° such that sin(
[
°) = 45 
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sin(
[
°) is equal to the ratio of the length of the side opposite the angle 
_
measuring 
[
° to the length of the hypotenuse, or 45 .
90
°
– 
x
°
5 
4 
x
°
90
°
Since two of the angles of the triangle are of measure 
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°. From 
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°), which is equal to the ratio of the length of 
the side 
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° to the hypotenuse, 
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is also 45 .

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QUESTION 20 
The correct answer is 100.
Since 
D
= 5
Ƥ
2, one can substitute 5
Ƥ
2 for 
D
in 2
D
= 
Ƥ
2
[ JLYLQJ
Ƥ
2 = 
Ƥ
2
[ 6TXDULQJHDFKVLGHRI
Ƥ
2 = 
Ƥ
2
[
gives 
Ƥ
2)
2
= (
Ƥ
2
[
)
2
ZKLFKVLPSOLƮHVWR
2
(
Ƥ
2)
2
= (
Ƥ
2
[
)
2
, or 
_
[
. This gives 
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and 5
Ƥ
2 for 
_ 
D
in the equa
_ 
tion 2
D
_ 
= 
Ƥ
2
[
_ 
, which yiel
_ 
ds 2(5
_ 
Ƥ
2) = 
Ƥ
(
WKLVLVWUXH
since 2(5
Ƥ
2)
Ƥ
2 and 
Ƥ
(
Ƥ
2
Ƥ 
Ƥ
2.
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QUESTION 1 
Choice B is correct.
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slope represents an interval over which the target heart rate is strictly 
increasing as time passes. A horizontal line segment represents an 
interval over which there is no change in the target heart rate as 
time passes, and a line segment with a negative slope represents 
an interval over which the target heart rate is strictly decreasing as 
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consists of a line segment with a positive slope followed by a line 
segment with a negative slope, with no horizontal line segment in 
between, indicating that the target heart rate is strictly increasing 
then strictly decreasing. 
Choice A is incorrect because the graph over the interval between 
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period in which there was no change in the target heart rate. Choice C 
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65 minutes consists of a line segment with a negative slope followed 
by a line segment with a positive slope, indicating that the target heart 
rate is strictly decreasing then strictly increasing. Choice D is incorrect 
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contains horizontal line segments and no segment with a negative 
slope. 
QUESTION 2